The belief that one of the most important aspects of a food is its calorie (energy) content has been one of the cornerstones of nutrition for the past 100+ years. And in fact, when I first started studying nutrition in the mid 2000’s, I recall my textbook talking about ‘calories in, calories out’ and how managing weight is as simple as ensuring that this invisible scale always balances. Just like an old-fashioned bank book, the prevailing belief is that you have a certain budget you need to stick to, and you can ‘earn’ extra food with exercise. Makes sense on the surface doesn’t it?
But what I have learnt over almost a decade in my clinic working with patients who have tried all sorts of diets, exercise regimes and meal plans, is that it’s not that simple. Not by a long shot.
Let me tell you about Jocelyn (not her real name). I first saw Jocelyn about 5 years ago. Her difficulty with her weight was causing her a great deal of stress, and she told me had spent most of her lifetime on one diet or another. By the time she visited my clinic, she had restricted her food intake down to the point where she was having a single piece of toast in the morning, and a protein shake at night. Going by the ‘calories in, calories out’ equation, Jocelyn was eating only a few hundred calories per day, and by this logic, should have been enjoying a healthy, slim body. Yet she was carrying an extra 20kg that just wouldn’t budge, no matter what she did. She was also suffering from a host of symptoms of nutrient deficiencies due to how little food she was getting in a day, as well as poor gut health.
And unfortunately, Jocelyn’s case is not uncommon.
Here's how the whole calorie shebang came about. Calories were originally discovered over a century ago, when a contraption known as a ‘bomb calorimeter’ was invented. This is a type of jar that is surrounded by water, and when food is burnt within the chamber of the jar, the amount of heat generated is measured. The researchers decided to call this measurement a 'kilocalorie', with 1 kilocalorie equaling the amount of energy required to increase the temperature of 1kg of water by 1° Celsius. For ease of notation, you'll sometimes see the term 'Calorie' (with a capital C) used to refer to a kilocalorie (kcal).
From this, researchers were able to extrapolate that foods containing carbohydrates yielded 4kcal/g, proteins 4kcal/g, fats 9kcal/g and alcohol 7kcal/g. And, as you may have already surmised, this is partly where we get the term ‘burn calories’ from. Then, the basic premise was that depending on your height, weight, age and sex, you would have a stock-standard ‘basal metabolism’ that can be determined by applying a simple equation. Your metabolism refers to the rate at which you convert food to energy, and when using this system, the assumption is that everyone who is the same height/age/weight/sex should have the same stats. Then, the more active you were, the more calories you would burn up, just like fuel in a car.
Ok that’s interesting….if you are wanting to heat some water by burning your food (waste of good food if you ask me). But the funny thing is, you are not a jar surrounded by water. You are an amazingly complex being made up of millions of cells, hormones, neurons and thoughts and feelings. And you are different from the next person...and the next person...and the next person. How the calorie concept even came close to being translatable to the human body amazes me, and I certainly spent quite a lot of my nutrition studies thinking ‘what the…?’ And now that I’ve been working on the frontlines with patients wanting to lose weight for the best part of a decade, I’m even more convinced that calories really don’t matter that much at all.
The question needs to be asked - why is that some people are naturally able to easily manage their weight (while eating like a horse) and others only need to look at cake sideways and instantly gain a couple of kgs? We all know someone (or maybe we ARE someone) who fits these descriptions.
Curiouser and curiouser…
The answer is that we have been focusing for far too long on a concept that never made much logical sense to begin with and doesn’t take into account the wonderful variance between individuals. And the rate at which we burn up the food we eat really does vary from person to person, meaning that the original calorie equations and calculations are at the very best, an extremely broad estimate. It all comes down to your unique metabolism - and this has many internal and external influences on how easily you gain (or lose) weight. For instance…
- Your muscle mass. We each carry our own unique muscle mass, and this is something I measure when I am performing Metascan™ Quadscan Body Composition & Cellular Health Analysis assessments on patients visiting the clinic. Muscle helps to provide a place for excess glucose to be utilized, which is why exercise is a great strategy to include when taking a preventative approach to, or aiming to improve, Type 2 Diabetes. The more muscle we have, the healthier we generally are – and when we diet, we tend to burn muscle, leading to a downward spiral of weight loss followed by a rapid regain (otherwise known as 'yo-yo dieting').
- Inflammation puts a stop to fat-burning, and I believe it is one of the most under-recognized causes of weight gain. Many people don’t realise their body is dealing with low-grade, chronic inflammation, and often this is linked to our gut health. Symptoms of inflammation in the body can include aches & pains, poor sleep, depression and high blood pressure, among others.
- Genetic tendencies. Unfortunately some of us are luckier than others when it comes to certain predispositions we have inherited (such as tendency to gain weight easily, or a family history of diabetes) – but it doesn’t mean that we can’t overcome this with the right approach. The important thing to keep in mind here is that you are not powerless, and there are things you can do, when armed with the right tools and strategy. In fact, I do see many patients who have been motivated to make changes in their life because they have witnessed the fallout from poor health suffered by others.
- How healthy your gut is. This is a relatively new area of research, and it is showing a lot of promise for explaining the huge spike in obesity and diabetes diagnosis that have occurred over the past few decades. Healthier populations of gut flora appear to make it easier to manage weight.
- Stress can have a huge impact on your weight, and any kind of chronic stress can slow your metabolism right down as well as mess your stress hormones about which influences your body’s ability to maintain balance. Particularly if you are in a state of burnout, your stress hormones are likely to be all out of whack.
- Your thyroid gland plays a big role in controlling your metabolism, and if your thyroid is not happy it can make it very difficult for you to shift weight easily. Your thyroid doesn’t like you restricting your food intake or dieting, which means it can be counter-productive to be continually dieting as all you'll do is slow your metabolism right down.
- Hormonal balance. The metabolism increases during the luteal phase of a healthy menstrual cycle, which is why you may find you feel hungrier than normal in the week or two prior to your period (particularly if you suffer from PMS)
- How well you are sleeping. Sleep is a factor in weight loss – not only do we tend to eat more when we aren’t sleeping (because we are awake for a longer period) but poor sleep can drive you to seek out foods that give you an instant energy boost – such as chocolate!
- Insulin & blood glucose. These two factors are involved in how effectively your body is able to process and deal with carbohydrates from the foods you eat. The trouble is, in our fast-paced Western lives, we tend to reach for quick and easy foods that are high in these types of carbohydrates – such as bread, pasta, white rice and sugary breakfast cereals. These foods cause a spike in our blood glucose, followed by a release of the hormone insulin by the pancreas, in order to utilize or store the carbohydrates you have eaten. Continually high insulin levels cause you to stay predominantly in fat-storage mode.
- Glycaemic load of foods. This is linked to the insulin/blood glucose point above, and in a nutshell, refers to whether a food provides you with a rapid blood sugar spike or a slow, sustained energy release. We want to go for the slow and steady, as not only is this the best way to eat for weight loss, it is also the best for preventing hunger, energy slumps and mood swings throughout the day.
- Thermogenic effect of food. Here’s another concept that the glass jar got wrong. Not all foods provide us with equal calories - even when they contain the same number of calories. When you eat carbohydrates, your body is very efficient at being able to break down and utilise these, meaning that most of the energy content is readily available. However, when you eat protein for instance, your body has to work harder - this results in a certain proportion of the energy content is sacrificed to the breaking down process, and therefore fewer net calories available to the body.
Here's a thought - instead of focusing on calories, we work out which foods are right for OUR body? The ones that cause us to feel good, give us sustained energy and provide us with the nutrients WE need? And in place of continually restricting our diet, we work on removing as many of the above roadblocks that keep us locked fat-storage mode, and cause us to feel ho-hum?
In my clinic, I use a program called Metabolic Balance to help my patients move out of dieting mode, into a sustainable, life-long way of eating that matches their body with their ideal foods. I've been witnessing amazing results with this program, but one of the biggest shifts I see is people start to enjoy their food again, instead of food causing stress and anxiety.
The moral of the story is - weight loss is a natural side effect of the body being in a state of optimal health and of a balanced metabolism.